Water supply systems and particular underground irrigation systems are known in the art. Typically, an irrigation system includes a controller for turning the supply of water on or off, a check valve to prevent backflow and a set of sprinkler heads that connect to the water supply lines. The irrigation systems are designed to supply water at high pressure, which may be in excess of 150 psi, to the supply line and the sprinkler heads. Since the water in the irrigations systems is destined for delivery to the soil proximate the irrigation lines oftentimes small leaks at the fittings of the irrigation system may be ignored since it is time consuming and costly to cut out and replace leaking fittings. However, leaks in the underground irrigation system can cause unintended consequences since the leaks may cause a reduction in supply line pressure at the sprinkler valves thereby reducing the range of the sprinkler valves. In addition, leaks may cause soil erosion as well as over watering regions around the leak.
While proper installation of a system requires checking the underground lines for leaks prior to covering the underground lines not all the joint leaks around fittings may be detected. For example, the placement of soil around the irrigation pipes and the fittings may cause sufficient disturbance of the irrigation pipe with respect to the fitting so that secondary leakage may occur at one or more of the joints between the fittings and the underground irrigation pipe. The condition of secondary leaks is more likely to occur if the joint between the underground irrigation pipe and the fitting has not been properly formed, however, it may not be detected until stress is placed on the joint. To minimize or eliminate the problem of secondary irrigation leakage the irrigation system fittings may be leakproofed or reinforced during the installing process and prior to burial of the irrigation lines by securing a closed or split sealing ring proximate each of the fittings in the irrigation system. These type of secondary leaks may be more likely to occur if the fill soil contains rocks or other hard objects.
In other cases underground irrigation lines may be buried without checking for leaks since the water or power necessary to operate the system is not available during the installation process. In these cases it also prudent to place a closed or split sealing ring proximate each of the joints between the underground irrigation lines and the fittings.
In still other cases the system may be tested by subjecting the system to high pressure after the irrigation pipes and sprinkler heads are operative. During the testing process leaks may be observed. These type of leaks may be repaired without replacing the fitting by using a split sealing ring that can be placed around the irrigation pipe and abutted to a fitting to form a leakproof seal of the pipe to the fitting.
Sealing irrigation pipes to fittings may be done through the method of solvent welding connectors to supply lines in irrigation systems. In solvent welding a thermoplastic polymer fitting, such as PVC, is coated with a thin layer of solvent that for a short time dissolves the surfaces of the polymer fitting creating a viscous liquid film on the surface of the fitting. While the surface of the polymer fitting is in the dissolved or liquid state it is joined to a surface of a polymer pipe that also has a thin layer of solvent thereon which also creates a viscous liquid film on the surface of the pipe. While both the surfaces of the polymer fittings have a thin viscous film the fittings are brought together and held in position. As the viscous film solidifies or cures it creates a solvent welded joint between the two fittings. If for some reason the film does not cover the entire shared surfaces between the pipe and the fitting a leak may occur causing erosion as well as reducing the supply line pressure and thus reducing the range of the irrigation system.
Another type of water system where secondary leaks may occur after the water pipes have been covered and concealed is in water pipes used in residential and commercial buildings where the water pipes may not be subjected to working pressures until after the water pipes have been concealed by walls, floors or ceilings. Oftentimes such leaks can be disastrous since it is not only the replacement of the leaking joint that is required but the secondary damage caused to walls, ceilings, floors and equipment. In those cases joint reinforcement through use of a sealing ring for each of the joints between the fittings and the pipes provides assurances that the chances of building or the building contents being damaged from water escaping from by a failed joint between a pipe and a fitting are substantially eliminated.